1. Field of Invention
The present invention relates to pneumatic amplifiers or pneumatic sensing devices which generally sense the back pressure from a jet for purposes of controlling the movement of a member, gauging size, or inspecting parts. This back pressure is amplified to a level whereby a signal is generated or such strength that it can actuate an electrical switch or pneumatic or hydraulic mechanism. The subject matter is generally found in Patent Office Class 137, Subclass 82, but is not necessarily entirely limited to this classification.